Cooling-induced augmentation of the contractile response of the golden hamster tracheal muscle to substance P in-vitro.

The effect of temperature on the substance P-induced contraction of the isolated tracheal strip-chain preparation from the golden hamster has been examined. A decrease of bath temperature from 37 to 20 degrees C augmented the contractile response of the trachea caused by substance P. Similar cooling-induced augmentation was observed in the contractile responses to caffeine and carbachol, but not to potassium chloride. The increased responsiveness with lowered temperature of the trachea to substance P may be due to the acceleration of Ca2+ release from an intracellular storage site.